Priming refers to the fact that the mere processing of an item can facilitate subsequent processing of that same item. Priming effects can occur in the absence of conscious recollection of the prior study episode, and it has, therefore, been suggested that priming and explicit memory disorder patients is critical for this hypothesis, since if it is possible to link the breakdown of explicit memory and priming to damage to different brain regions this would strengthen the independent memory systems hypothesis. Difficulties associated with evaluating priming effects in memory impaired subjects include that priming measures may be less sensitive than explicit memory measures, and that the priming obtained in a given task is related to baseline performance, with poorer baseline performance resulting in greater priming. Therefore, it patients have even mild information processing deficits this may make priming impairments. The proposed project will investigate these issues in normal subjects and alcoholic patients with varying degrees of memory and processing deficits. The proposed project will investigate these issues in normal subjects and alcoholic patients with varying degrees of memory and processing deficits. The proposed experiments are designed to manipulate baseline performance level and sensitivity of the priming measures. Measures of priming, baseline performance, and explicit memory will be obtained. The subjects will be normal controls and chronic alcoholic patients who differ in the severity of their explicit memory defects, ranging from non amnesic patients without noticeable memory impairments through """"""""borderline Korsakoff"""""""" patients with only mild memory deficits to severely amnesic patients with Korasoff's syndrome. Measures of volume loss in specific brain structures will be obtained from MRI. These measures will be related to the behavioral indices, using a multiple regression approach, to determine the specific role of each brain region in perceptual. lexical processing, explicit memory and magnitude of priming.
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